(1) Field of the Invention
The present invention relates to a method for processing silver halide color photographic materials, and in particular a method for developing silver halide color photographic materials in which the replenishing amount of the color developer is reduced considerably.
(2) Description of the Prior Art
Processing a silver halide color photographic material basically is composed of two steps of color development (for a color reversal material, black and white first development before it), and desilvering, and the desilvering comprises of a bleaching step and a fixing step, or a monobath bleach-fixing step that may be used alone or in combination with the bleaching step and the fixing step. If necessary, additional processing steps may be added, such as a washing step, a stopping step, a stabilizing step, and a pretreatment step to accelerate development.
In the color development, silver halide that has been exposed to light is reduced to silver, and at the same time the oxidized aromatic primary amine color-developing agent reacts with a coupler to form a dye. In this process, halogen ions resulted from the decomposition of the silver halide dissolve into the developer and accumulate therein. On the other hand, the color-developing agent is consumed by the above-mentioned reaction with the coupler. Further, other components in the color developer will be held into the photographic material and taken out, so that the concentrations of components in the developing solution lower gradually. Therefore, in a development method that continuously processes a large amount of a silver halide photographic material, for example by an automatic-developing processor, in order to avoid a change in the finished photographic characteristics for the development caused by a change in the concentrations of the components, some means is required to keep the concentrations of the components of the color developer within certain ranges.
For instance, if the influence of the condensation of a component that will be consumed, such as developing agents and preservatives, is small, generally its concentration in the replenisher has previously been made higher. In some cases, a material that will flow out and that has an effect of restraining development is contained in a lower concentration-in a replenisher, or is not contained in the replenisher. In other cases, a compound may be contained in a replenisher in order to remove the influence of a material that will flow out from the photographic material. Further, in other cases, for example, the pH, the alkali, or the concentration of a chelating agent is adjusted. As measures for them, usually a method of replenishing with replenishers is used that will supply insufficient components and dilute the increased components. The replenishment with the replenishers, however, necessarily results in a large amount of overflow, which creates large economic and public pollution problems.
In recent years, for the purpose of saving resources and avoiding the public pollution, it has been earnestly desired to reduce the replenishing amount of the developer as well as to accelerate the developing process. However, if the replenishing amount of a color developer is simply lowered, an exudate from the photographic material, in particular bromide ions that are a strong development restrainer, accumulates, resulting in a problem that lowers the development activity and impedes the development speed. To solve this problem, a technique of accelerating the development is required, and many such techniques that enable the replenishing amount to be lowered have been studied. One such known technique, for example, is to increase the pH and the processing temperature of the developer, thereby making the development rapid. This technique, however, causes such serious problems as a high degree of fogging, reduced stability of the developer, and a fluctuation of photographic characteristics as continuous processing increases. Another acceleration technique that involves adding various development accelerators is known, but it has not been satisfactorily effective.
For the purpose of lowering the accumulation of bromide ions, which are a strong development restrainer, thereby intending to make the development rapid, JP-A ("JP-A" means unexamined published Japanese patent application) Nos. 95345/1983, 232342/1984, and 70552/1986 and WO No. 04534/1987 disclose methods wherein silver halide photographic materials having high contents of silver chloride are used, and the methods are considered as effective means of lowering the replenishing amount of the developer without marring the rapidness of the development. It was found, however, that the methods were not of practical use because new problems arose that when the replenishing amount of the developer was intended to be lowered without marring the rapidness of the development, the photographic characteristics changed conspicuously in the continuous process, and a suspended matter considered as silver exuded from the photographic material occurred in the processing solution, which soiled the rollers of the processor, clogged a filter, and soiled or damaged the photographic material.
When the replenishing amount is lowered, as another major problem involved in the continuous process can be mentioned that there is a high degree of fogging of a silver halide color photographic material that has been developed. Since fogging is liable to differ greatly when a photographic material whose fogging is high is processed under such development conditions that the temperature or the pH rises, which readily causes fogging to occur, and under such development conditions that the temperature or the pH drops, which barely causes fogging to occur, therefore there will be great changes in the characteristics after development of such a photographic material.
As one means of preventing such fogging of a silver halide color photographic material is known to add various antifoggants to the photographic material. That is, it is known that compounds such as benzotriazole, 6-nitrobenzimidazole, 5-nitroisoindazole, 5-methylbenzotriazole, 5-nitrobenzotriazole, 5-chlorobenzotriazole, 2-thiazolyl-benzimidazole, 2-thiazolylmethyl-benzimidazole, indazole, hydroxyazaindolizine, and adenine have a remarkable effect in preventing fogging.
It is recognized that when common developer replenishing is carried out, such antifoggants and stabilizers as mentioned above exhibit an effect to minimize the change in the characteristics after development, but on the contrary when the developer replenishing amount is lowered considerably more than the usual amount, there were such problems that the antifoggant and stabilizer added to the photographic material caused after-development characteristics, the sensitivity in particular, to change greatly, as well as markedly reducing the silver developing speed.
At present, although the replenishing amount of a color developer varies a little depending on the photographic material to be developed, generally the replenishing amount is on the order of 180 to 1000 ml per m.sup.2 of the photographic material to be processed. This is because if the replenishing amount is lowered while avoiding marring the rapidness of the development, the occurrence of quite serious problems, such as stated above that the photographic characteristics change greatly and that a suspended matter arises in the developer, is anticipated in the continuous process, and because a technique fundamentally solving these problems has not been found.